JP5302451B1 - Straight tube type lighting device using straight tube type LED lamp - Google Patents

Abstract

A straight tube lighting device having a simple shape is provided.
SOLUTION: A straight tube type LED lamp unit 510 incorporating an LED group 250 and a drive circuit 550, and first and second attachments 502, 504 provided at both ends of the straight tube type LED lamp unit 510, The first and second attachments include a lamp fixing portion 520, a mounting base 540, and a support 530, and the drive circuit includes a capacitor 222 and a full-wave rectification circuit 230, and the full-wave The LED group 250 is connected to the output terminal of the rectifier circuit 230, and the capacitance of the capacitor 222 is set to a value in a region where the peak value of the current flowing through the LED group increases based on the increase in the capacitance. A straight tube lighting device 500 that has a cutoff period based on the number of stages connected in series and supplies a pulsating current whose peak value is determined based on the capacitance of the capacitor 222 to the LED group.
[Selection] Figure 1

Description

The present invention relates to an illumination device using an LED element.

  A straight tube type LED lamp including a light emitting diode (hereinafter referred to as LED) includes a large number of LED elements inside the straight tube type LED lamp, and the LED element emits light by supplying a driving current to the LED element. Operates as a straight tube lighting device. When the forward supply voltage is gradually increased from a substantially zero (V) state, an LED element that operates as a light source starts to flow a current to the LED element at a predetermined voltage VLC (V), and starts a light emitting operation. When the supply voltage is further increased, the current flowing through the LED element increases and the light emission amount of the LED element increases.

  Unlike a general diode element, an LED element has a large voltage drop in the forward direction, and thus consumes a large amount of power. This power consumption is not only used for light emission, but a considerable amount of power is converted into heat, raising the temperature of the LED element.

  When the temperature of the LED element rises due to the heat generated by the LED element, it not only has a risk of generating dust, but also adversely affects the life of the LED element. For this reason, a heat dissipation mechanism made of a metal material having excellent thermal conductivity is provided inside the straight tube type LED lamp to dissipate heat of the LED element and suppress an increase in temperature of the LED element. For example, in Japanese Patent Laid-Open No. 2012-69303 (Patent Document 1), a metal base 30 that radiates heat is provided in the straight pipe 10 to dissipate heat generated by the LED module 20, and the temperature of the LED module 20. A technique for suppressing the increase is disclosed.

JP 2012-69303 A

  The straight tube illumination device described in Patent Document 1 has a structure in which the heat generated by the LED module 20 is dissipated using a metal base that dissipates heat. It has a complicated structure. In order to suppress the temperature rise of the LED module 20, a heat dissipation structure is indispensable, and it is difficult to make the straight tube type lighting device a simple structure.

  An object of the present invention is to provide a straight-tube illumination device having a very simple structure.

Although the basic invention for solving the above-mentioned problem is described in each claim , the LED element that suppresses heat generation is used, and the cylindrical resin case, the resin substrate disposed in the cylindrical resin case, and the resin substrate are held. The first and second fittings that are integrally fixed to the projection and the cylindrical resin case are integrally molded with resin, and the resin of both the cylindrical resin case of the straight tube type LED lamp part and the resin molding attachment part This is to provide a simple structure by integrating the body, and to make it possible to attach and replace the straight tube lighting device in a place where lighting is required.

The first aspect of the present invention includes an LED group configured by connecting a plurality of LEDs that emit light in series based on a supplied light emission current, and a drive circuit for supplying the light emission current to the LED group. A straight tube type LED lamp part formed with an elongated cylindrical resin case, and first and second attachments respectively provided at both ends of the straight tube type LED lamp part,
The drive circuit includes a peak current setting capacitor, a parallel resistor connected in parallel to the peak current setting capacitor to form a parallel circuit together with the peak current setting capacitor, and an alternating current input from an input terminal. A full-wave rectifier circuit that rectifies the wave and outputs a pulsating current from an output terminal, the parallel circuit configured by the peak current setting capacitor and the parallel resistor, and an input terminal of the full-wave rectifier circuit When, are connected in series to an AC power source,
The LED group is connected between the output terminals of the full-wave rectifier circuit,
Has a projection projecting inside the tubular resin case is molded one body, the resin substrate is held by the projections, the LED group is arranged which has the driving circuit on the surface of the resin substrate ,
The first and second attachments are respectively a lamp fixing part for fixing an end of the cylindrical resin case of the straight tube type LED lamp part, and a mounting base for attaching the straight tube type LED lamp part. The support that connects the lamp fixing part and the mounting base is integrally formed by resin molding, and the thickness cross-sectional area of the support is arbitrary for the elongated part of the cylindrical resin case. The support is formed in a shape smaller than the cross-sectional area,
The tube-shaped resin case of the straight tube type LED lamp portion has an end bonded to the lamp fixing portion with an adhesive, and the straight tube type LED lamp portion and the first and second resin molded integrally . The fixtures are fixed to each other as a unit, and are attached to a place where lighting is performed, and are configured to be replaceable .
When the number of LEDs connected in series constituting the LED group connected between the output terminals of the full-wave rectifier circuit is the number of stages, the LED group is formed in any number of stages from 5 to 40 stages. The capacitance of the capacitor for setting the peak current constituting the parallel circuit is set to a value within a range of 0.5 microfarad to 20 microfarad, and the resistance value of the parallel resistor constituting the parallel circuit is set to 3 KΩ or more. The pulsating current flows through the LED group, with a peak current value determined based on the capacitance of the capacitor for setting the peak current, and having a cutoff period determined by the number of stages of the LEDs connected in series constituting the LED group. It is the straight tube | pipe type illuminating device characterized by the above.

According to a second invention for solving the above-mentioned problem, in the first invention, the mounting plate has an elongated shape with an area for accommodating the plane of the straight tube type LED lamp portion in a plane viewed from above, A straight tube type lighting device that is fixed to a second fixture and is attached to a place where illumination is performed in a state where the mounting plate is fixed and can be replaced. .

According to a third aspect of the present invention for solving the above-described problem, in the first or second aspect of the present invention, the protrusion provided on the cylindrical resin case has a groove in the longitudinal direction, and the groove is made of the resin. It is a straight tube type lighting device characterized by holding the resin substrate by inserting the substrate .

The fourth invention is the invention according to one of the first to third, the mount is a straight-tube lighting apparatus characterized by being uneven portion is formed on the bottom surface.

According to a fifth aspect of the present invention, in the invention described in one of the first to fourth aspects, each of the lamp fixing portions of the first and second fixtures is the cylindrical shape of the straight tube type LED lamp portion. has a larger hole periphery of the end portion of the resin case, an end portion of the tubular resin case is inserted into the hole of the lamp holding portion, the end portion of the tubular resin casing into the hole of the lamp holding portion In the inserted state, the lamp fixing portion and the end of the cylindrical case are closely fixed by an adhesive ,
A projection integrated with the lamp fixing portion is formed inside the lamp fixing portion, a substrate fixing groove is formed on the protrusion, and both end portions of the resin substrate protrude to holes of the lamp fixing portion, respectively. a straight-tube lighting apparatus, characterized in that inserted into and fixed to each of the board fixing grooves.

According to a sixth aspect of the present invention, in the straight tube lighting device according to one of the first to fifth aspects, the LED group connected in parallel to the output terminal of the full-wave rectifier circuit has 9 to 40 stages. It is a straight tube illuminating device using LEDs, characterized in that it is formed of LEDs connected in series in any number of stages .

According to a seventh aspect of the present invention, in the straight tube lighting device according to the sixth aspect, each stage of the LED group is configured by the LEDs having a plurality of LED elements connected in parallel, and the LED group is the parallel unit. A straight-tube illuminating device using an LED, wherein the LED having a plurality of connected LED elements is connected in series in the number of stages .

An eighth invention is a straight tube type lighting device using the LED according to claim 6 or 7, wherein the LED is characterized in that the peak current setting capacitor is a ceramic capacitor. This is a straight tube illumination device.

  According to the present invention, it is possible to obtain a straight tube illumination device having a very simple structure.

It is a front view of the straight tube | pipe type illuminating device 500 which is one Embodiment of this invention. It is a top view of the straight tube | pipe type illuminating device 500 which is one Embodiment of this invention. It is a bottom view of the straight tube | pipe type illuminating device 500. FIG. It is AA sectional drawing of the straight tube | pipe type illuminating device 500 shown in FIG. It is explanatory drawing which shows the connection structure of the cylindrical case 512 and the attachment tool 502. FIG. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. 10 is another embodiment of the attachment 502. It is DD sectional drawing of FIG. It is a bottom view of the fixture 502 shown in FIG. FIG. 6 is an explanatory diagram showing a configuration of an electrical component 30 held on a resin substrate 570. It is a circuit diagram which shows the electric circuit of the straight tube | pipe type illuminating device. It is a wave form diagram which shows operation | movement of the electric circuit shown in FIG. 6 is a waveform diagram of current I4 flowing through LED group 250. FIG. It is a graph which shows the change of the peak value of electric current I4 when the capacity | capacitance of the capacitor for peak current setting is changed. It is a graph which shows the change of the peak value of electric current I4 when the capacity | capacitance of the capacitor for peak current setting is changed. It is a graph which shows the change of the peak value of electric current I4 when the capacity | capacitance of the capacitor for peak current setting is changed. It is a graph which shows the change of the peak value of electric current I4 when the capacity | capacitance of the capacitor for peak current setting is changed. It is a graph which shows the change of the peak value of electric current I4 when resistance 220 is changed. It is a graph which shows the transient current at the time of power activation when the resistance of a fuse is 100Ω. It is a graph which shows the transient current at the time of power activation when the resistance of a fuse is 50Ω. It is a graph which shows the change of the peak value of the electric current I4 at the time of changing the fuse 224. FIG. It is a graph which shows the waveform of the electric current I4 at the time of making the number of steps of LED group 250 into 2 steps and 9 steps.

  The modes for carrying out the invention described below (hereinafter referred to as “examples”) can solve the problems described in the column of problems to be solved by the above-described invention, and are described in the column of effects of the invention. The effects of the invention can be obtained. However, the embodiments described below are not limited to these, and can solve problems other than those described in the column of problems to be solved by the above-described invention, and are also included in the column of effects of the invention. It can also be obtained with effects other than the effects of the described invention. Furthermore, it is natural that the present invention can be applied to a straight tube type illumination device using the straight tube type LED lamp described in the column of the name of the invention. However, the technique described in the following embodiments is an illumination device other than the straight tube type illumination device. For example, it can be applied to a circular downlight.

  Details will be further described in the following embodiments, but typical problems to be solved by the following embodiments, configurations to solve the problems, and effects will be described. In addition, in order to assist an understanding, each structure is attached | subjected with the reference code described in drawing demonstrated below. The above-mentioned typical problem may overlap with the problem to be solved by the above-mentioned invention, and there is another one. In addition, the representative effect may overlap with the description effect in the column of the effect of the invention, and there are others.

1. Simple structure by integrating straight tube type LED lamp unit and fixture (1) Integration of straight tube type LED lamp unit 510 and fixtures 502 and 504 Conventional straight tube type LED lamps are directly connected like fluorescent lamps. A method of purchasing a tube type LED lamp and exchanging only a straight tube type LED lamp is used. This is because the straight tube type LED lamp has a short life like the fluorescent lamp, and it is necessary to repeatedly replace the straight tube type LED lamp.

  In the embodiment described below, the fixtures 502 and 504 are attached to the straight tube type LED lamp portion 510, and it is difficult for an amateur to easily remove it. The background is that the straight tube type LED lamp unit 510 having the LED group 250 and the drive circuit 550 for supplying current to the LED group 250 can be used for a long period without failure or deterioration.

  Although the LED group 250 and the drive circuit 550 for supplying current to the LED group 250 described in the following embodiments have a very simple circuit configuration, the LED group 250 generates very little heat. Further, the drive circuit 550 generates very little heat. Further, the light emission amount of the LED group 250 can be appropriately maintained without using a semiconductor switching element for forcibly cutting off the current. This is because the peak value of the current flowing through the LED group 250 is set by the capacity of the peak current setting capacitor 222 provided in series with the AC power supply. Thereby, the heat generation inside the straight tube type LED lamp unit 510 can be greatly reduced. As a result, the life of the straight tube type LED lamp unit 510 can be greatly extended. Since the straight tube type LED lamp unit 510 and the fixtures 502 and 504 are not premised on removal, the straight tube type illumination device 500 described in the following embodiment needs to be illuminated. By attaching it to a place where it is used, the straight tube type LED lamp 510 can be used for many years without replacement.

(2) Reduction of Heat Generation by Using Peak Current Setting Capacitor 222 In the embodiment described below, a ceramic capacitor having a long life can be used as the peak current setting capacitor 222. There is no need to use a smoothing capacitor as in the conventional product, and there is no need to use an electrolytic capacitor that is difficult to extend its life. Furthermore, by using the LED group 250 in a state in which the temperature rise is small, the lifetime of the LED elements constituting the LED group 250 can be significantly extended.

  In the embodiment described below, in addition to supplying the pulsating current generated by the full-wave rectifier circuit to the LED group 250, the LED group 250 is constituted by LED elements connected in series, and the LED elements are connected in series. By supplying the LED group 250 with a pulsating current having a current interruption period that varies depending on the number of stages, heat generation of the LED group 250 can be reduced. Increasing the number of LED elements in series connected to the LED group 250 increases the current interruption period. By setting the number of LED elements in the LED group 250 connected in series to 9 or more, it is possible to ensure the current interruption period.

2. Provision of a straight tube type lighting device having a simple structure (1) Miniaturization and simplification of the straight tube type lighting device 500 In the embodiment described below, a resin substrate 570 is provided inside a straight tube type LED lamp. An LED group configured by connecting LED elements 252 in series to a substrate 570 and a drive circuit 550 are provided. However, since the amount of heat generated by these LED groups and the drive circuit 550 is very small as compared with the conventional lighting device of this type, it is not necessary to provide a special heat dissipation mechanism in the following embodiments. For this reason, the straight tube type LED lamp has a very simple structure.

  A structure in which the straight tube type LED lamp unit 510 is fixed using a mounting tool 502 or a mounting tool 504 so that the straight tube type LED lamp unit 510 can be freely mounted on a ceiling, a wall surface, or other places where illumination is required. It has become. As described above, the straight tube type LED lamp unit 510 has less heat generation and does not require a metallic heat conductor or heat radiation fin for heat radiation, so the straight tube type LED lamp unit 510 is lighter than the conventional product. It is small. Thus, the fixtures 502 and 504 provided at both ends of the straight tube type LED lamp unit 510 can have a very simple configuration. Compared with conventional products, the lighting devices shown in the following embodiments are very simple, and therefore, there is an effect that it is easy to harmonize with the surrounding state from an aesthetic point of view at the installation location. This effect is a very important effect for the lighting device, and is an important market need always required for the lighting device.

(2) Miniaturization of the attachments 502 and 504 In the embodiment described below, the straight tube type LED lamp portion 510 is provided with a resin substrate 570 including an LED group and a drive circuit 550. No metal plate is provided. For this reason, the internal structure of the straight tube type LED lamp part 510 is very simple, and the straight tube type LED lamp part 510 can be made into a thin shape. Furthermore, the mounting tool 502 and the mounting tool 504 can be reduced in size.

3. Improvement of productivity (1) Fixing of resin substrate 570 inside cylindrical case 512 In the embodiment described below, the LED element 252 and the drive circuit 550 provided on the resin substrate 570 generate very little heat. There is no need to provide a metal plate for heat conduction on the resin substrate 570. Therefore, two grooves 326 are formed so as to face the inside of the cylindrical resin case 512 of the straight tube type LED lamp portion 510, and the resin substrate 570 is inserted so that both ends of the resin substrate 570 enter the grooves 326. To do. By inserting the resin substrate 570 having the LED group 250 and the drive circuit 550 between the two grooves 326 facing each other in this manner, the resin substrate 570 can be easily fixed to the straight tube type LED lamp portion 510. Can do. In this way, the resin substrate 570 including the LED group 250 and the drive circuit 550 can be fixed to the straight tube type LED lamp unit 510 by a simpler method with a simpler method, which is very excellent in terms of productivity improvement. Yes.

  In addition, since both ends of the resin substrate 570 can be fixed along the long axis of the straight tube type LED lamp portion 510, warpage in the longitudinal direction of the resin substrate 570 can be suppressed. In the conventional structure, the resin substrate 570 is fixed to the metal plate for heat conduction, so that the warp of the resin substrate 570 can be suppressed. However, in the following embodiments, the metal plate for heat conduction is unnecessary. In addition, suppression of the warpage of the resin substrate 570 occurs as a new problem. With the above-described structure, in addition to the improvement in productivity, the suppression of the warpage of the resin substrate 570, which is a new problem, can be solved together.

(2) Fixing the cylindrical case 512 In the embodiment described below, an opening is formed in one or both of the cylindrical cases 512, and a groove 326 facing the inside of the cylindrical case 512 is formed. The resin substrate 570 has an elongated shape, and the length along the major axis of the resin substrate 570 is longer than the length of the cylindrical case 512 in the major axis direction. Therefore, when the resin substrate 570 is inserted into the cylindrical case 512, both ends of the resin substrate 570 protrude from the opening of the cylindrical case 512. Grooves 334 are also provided in the attachments 502 and 504 provided at the ends of the cylindrical case 512, and both ends of the resin substrate 570 protruding from the opening of the cylindrical case 512, for example, both sides along the long axis are grooves. It is inserted into 334 and fixed. Since the resin substrate 570 is inserted into both the groove 326 of the cylindrical case 512 and the groove 334 of the lamp fixing portions 520 and 522, the cylindrical case 512 and the lamp fixing portions 520 and 522 are fixed. The cylindrical case 512 and the lamp fixing portions 520 and 522 can be fixed with a simple structure. By adhering between the cylindrical case 512 and the lamp fixing portions 520 and 522 with an adhesive with a simple structure, the cylindrical case 512 and the lamp fixing portions 520 and 522 can be tightly fixed with a simple structure. .

4). Breathing structure of straight tube type LED lamp unit 510 (1) Breathing structure via attachments 502 and 504 In the embodiment described below, both ends of the cylindrical case 512 of the straight tube type LED lamp unit 510 are open, A communication path 544 is formed inside the attachment 502 or the attachment 504, and an opening provided on the attachment base 540 or the attachment base 542 of the attachment 502 or the attachment 504 and the inside of the straight tube type LED lamp portion 510. Are connected via the communication path 544. With this structure, air inside the straight tube type LED lamp portion 510 can enter and exit through the communication path. It is possible to prevent the air inside the straight tube type LED lamp unit 510 from condensing due to a temperature change. If air in and out of the straight tube type LED lamp unit 510 is suppressed, dew condensation may occur inside the straight tube type LED lamp unit 510 due to changes in the outside air temperature. Since the air inside the tube-type LED lamp unit 510 can easily enter and exit from the outside via the communication path, a rapid increase in humidity inside the straight-tube LED lamp unit 510 can be suppressed, and condensation can be suppressed. can do. Thereby, it is possible to suppress the life of the straight tube type LED lamp unit 510 from being shortened. In addition, by opening the back surface of the mounting tool 502 or the mounting tool 504, it is possible to suppress the entry of dust, which is unlikely to cause water to be accidentally applied to the opening.

(2) Weight reduction of attachments 502 and 504 and routing of power cord In the embodiment described below, a communication path 544 is provided inside the attachment 502 and attachment 504 for attaching the straight tube type LED lamp portion 510. As a result, the mounting tool 502 and the mounting tool 504 can be reduced in weight, and resin molding is facilitated. In addition, the power cord can be pulled out from the straight tube type LED lamp unit 510 using the communication path 544.

5. Suppression of the heat generation amount of the LED element 252 (1) Suppression of heat generation In the embodiment described below, a pulsating current is applied to the LED element 252 via the full-wave rectification circuit 230. Since the voltage applied to the LED element 252 changes periodically, the LED element 252 repeatedly turns on and off in synchronization with the voltage change. For this reason, there is a period in which heat is generated and a period in which heat is not generated periodically, the total heat generation amount of the LED elements 252 is suppressed, and the temperature rise of the LED group 250 is suppressed. By repeatedly ensuring the turn-off time of the LED element, the effective value of the current flowing through the LED element 252 can be reduced, and heat generation of the LED element can be suppressed.

(2) Setting of the current interruption period by the number of serially connected LED elements 252 In the embodiment described below, the LED group 250 is configured by connecting the LED elements 252 in a plurality of stages in series, and varies periodically. Power is being supplied. Thereby, heat_generation | fever of LED group 250 can be suppressed. Further, the pulsating current supplied to the LED element 252 has a cutoff period that changes based on the number of stages in series connection, and this cutoff period increases by increasing the number of stages in series connection. This cutoff period can be set to an appropriate value by setting the number of LED elements 252. Thereby, heat_generation | fever of the LED element 252 can be suppressed and it can manage to an appropriate state.

(3) Reduction of heat generation by the peak current setting capacitor 222 In the embodiment described below, the operation is performed in a region where the peak value of the current flowing through the LED element 252 is determined by the capacity of the peak current setting capacitor 222 of the drive circuit 550. Yes. In a region where the peak value of the current flowing through the LED element 252 changes depending on the resistance, the resistance generates heat, and a cooling structure is required. However, when the peak value of the current flowing through the LED element 252 is set in a region determined by the capacitance of the peak current setting capacitor 222, the power consumption in the drive circuit 550 is extremely small and heat generation is small. Further, the maximum light emission amount of the LED group 250 can be appropriately set by a method that does not generate heat.

(4) Reduction of power consumption and heat generation by setting the LED current cutoff period According to the inventor's examination results, when the number of stages in which the LED circuit 254 is connected in series is increased, the current flowing through the LED element 252 is cut off. The cut-off period increases. If the LED group 250 is composed of one LED circuit 254, that is, if the LED group 250 is composed of one stage of LED circuit 254, the current flowing through the LED element 252 is momentarily cut off. Current interruption period is very short. For this reason, the effective value of the current flowing through the LED element 252 is almost the same as the state where the pulsating current continues to flow through the LED element 252. When the number of stages of the LED circuits 254 connected in series is 5 or more, preferably 9 or more, the interruption period of the current flowing through the LED element 252 is appropriately secured. Thereby, the effective value of the current flowing through the LED element 252 can be significantly reduced. On the other hand, the brightness of the illumination is affected not only by the effective value of the current but also by the peak value of the repeatedly supplied current. Therefore, even if the interruption period of the current flowing through the LED element 252 is increased to suppress the effective value of the current, the decrease in the brightness of the illumination can be reduced.

6). Noise reduction of lighting device 200 using LEDs (1) Suppression of noise generation by not using switching elements In the embodiment described below, the value of current flowing through an LED group 250 configured by connecting LED elements in series is determined. Control is performed by setting the capacitance of the capacitor 222 connected in series to the rectifier circuit 230 provided in the drive circuit. For this reason, it is not necessary to use a semiconductor switching device for controlling the effective value of the current. Therefore, almost no noise such as electromagnetic waves generated in a lighting device using a conventional LED is generated. In the medical field, various devices are used to maintain life. In addition, high-precision measurement is performed. In such a medical field, it is desirable to reduce noise as much as possible, and the conventional lighting device has a problem regarding noise generation. In the embodiment described below, almost no electrical noise is generated, so there is almost no electromagnetic noise or noise entering the power supply. For example, an optimal effect can be obtained by using the illumination device according to the present invention in a place where electromagnetic noise and noise on a power supply line must be strictly controlled, such as in a medical field.

(2) Suppression of noise generation by not using a noise source such as an oscillator The following embodiments do not require the use of a high-frequency generation circuit, such as not using a transmission circuit. For this reason, high frequency noise and the like do not occur. Suitable for lighting in places that handle precision equipment.

  Other problems and effects solved by the following embodiments will be described in the following description.

1. FIG. 1 is a front view of a straight tube illumination device 500, and FIG. 2 is a plan view of the straight tube illumination device 500. FIG. The straight tube illumination device 500 can be directly attached to a ceiling, a wall, or other places where illumination is required. In addition, one or a plurality of sets of straight tube lighting devices 500 can be installed via the mounting plate 600. The mounting plate 600 is not necessarily required, and it is natural that the straight tube lighting device 500 can be mounted at a place where lighting is required by using the mounting tool 502 or the mounting tool 504 of the straight tube lighting device 500. By using the mounting plate 600, a plurality of straight tube illuminating devices 500 can be temporarily attached to the mounting plate 600, and then the plurality of straight tube illuminating devices 500 can be mounted at a place where illumination is required at once. .

  In this embodiment, two sets of straight tube illumination devices 500 are attached to the attachment plate 600. Each straight tube type lighting device 500 includes a straight tube type LED lamp unit 510 and a straight tube type LED lamp unit 510 each holding a resin substrate 570 including an LED group 250 (see FIG. 12) and a drive circuit 550. Are attached to a mounting plate 600, and in some cases, to a place where lighting is required, such as a ceiling or a wall.

  2. Description of the Related Art Conventionally, lighting fixtures such as fluorescent lamps have a structure in which only fluorescent lamps can be easily replaced because fluorescent lamps are likely to deteriorate or fail and have a short life. However, in this embodiment, the life of the straight tube type LED lamp unit 510 is very long, so there is almost no need to replace only the straight tube type LED lamp unit 510. For this reason, the straight tube type LED lamp part 510, the attachment tool 502, and the attachment tool 504 are not fixed to each other with an adhesive or the like, and only the straight tube type LED lamp part 510 is not easily removed.

  A resin substrate 570 provided inside the straight tube type LED lamp unit 510 has an LED group 250 (see FIG. 12) configured by connecting a large number of LED circuits 254 including LED elements in series, and a current to the LED group 250. Is provided with a drive circuit 550 (see FIG. 12). In this embodiment, the heat generation of the LED group 250 and the drive circuit 550 can be significantly reduced, and the temperature rise of the LED group 250 and the drive circuit 550 is extremely small. For this reason, the LED group 250 and the drive circuit 550 can be provided on the resin substrate 570, and the resin substrate 570 is not provided with a cooling metal plate or heat radiating fins for heat transfer and heat dissipation. For this reason, the thickness of the straight tube type LED lamp part 510 can be made smaller than that of the conventional product, and the structure is extremely simple.

  The fixture 502 is bonded to one end of the straight tube type LED lamp unit 510 with an adhesive or the like, and similarly the fixture 504 is bonded to the other end of the straight tube type LED lamp unit 510 with an adhesive or the like. Has been. In this embodiment, the straight tube type LED lamp unit 510 is fixed to the mounting plate 600. However, the straight tube type LED lamp unit 510 is directly attached to the ceiling, wall, or other place where illumination is required by the fixtures 502 and 504. Can be installed.

  The attachment 502 and the attachment 504 have the same shape, and will be described next. The fixture 502 includes a lamp holder 520 fixed to one end of the straight tube type LED lamp unit 510, a mounting plate 540 for fixing the straight tube illumination device 500 to the mounting plate 600 or a place where illumination is required, A support body 530 for fixing the lamp holder 520 to the mounting base 540 is provided. Similarly, the fixture 504 includes a lamp holder 522 that is fixed to the other end of the straight tube type LED lamp unit 510, a mount base 542, and a support body 532 for fixing the lamp holder 522 to the mount base 542. ing. The fixture 502 and the fixture 504 are made of resin, the lamp holder 520, the support 530, and the mount 540 are made of resin, and the lamp holder 522, the support 532, and the mount 542 are made of resin. It is made by integral molding, and in this embodiment, these surfaces are further plated with chrome. As will be described in detail below with reference to FIGS. 5 to 10, a communication hole 544 is formed inside the fixture 502 and the fixture 504.

  A resin substrate 570 is fixed inside the straight tube type LED lamp unit 510, and the LED group 250 (see FIG. 13) configured by a number of LED circuits 254 electrically connected in series to the resin substrate 570. ) Is provided. However, if all the LED circuits 254 shown in the figure are given a reference symbol, it will be complicated, so only one will be given a reference symbol. As will be described in detail below, since the heat generation of the LED group 250 and the drive circuit 550 is very small in this embodiment, the resin substrate 570 does not require a metal plate for heat dissipation, and the surface of the resin substrate 570 is The front and back surfaces of the resin substrate 570 are in contact with air only by performing the water resistance treatment.

  The resin substrate 570 may be a single substrate, but may be composed of a plurality of resin substrates, for example, four resin substrates. Each resin substrate can be easily fixed as in the case of a single resin substrate by sequentially inserting between two grooves formed in a cylindrical case 512 described below. Thus, by dividing the resin substrate 570 into a plurality of portions, the warpage of each resin substrate can be reduced. In this embodiment, since each resin substrate 570 does not require a heat-dissipating metal plate, it is very easy to make one resin substrate 570 or to divide it into a plurality of substrates.

  AC power for operating the drive circuit 550 is supplied using the power cord 590 provided in the attachment 502 or the communication hole 544 inside the attachment 504 (see FIGS. 7 and 8). The power cord is a cord for supplying a normal household AC current, and although not shown, a plug for connecting to an outlet is attached to the tip of the power cord 590. The inner end of the power cord 590 is connected to the resin substrate 570 and supplies AC power to the drive circuit 550.

  The embodiment of FIG. 2 is a plan view of the embodiment shown in FIG. 1, and two sets of straight tube lighting devices 500 are fixed to the mounting plate 600. The mounting base 540 of the mounting tool 502 and the mounting base 542 of the mounting tool 504 are provided with screw holes 548 (see FIG. 8), and the mounting base 540 and the mounting base 542 are fixed to the mounting plate 600 by screws 546. In this state, it is possible to screw the ceiling or wall that requires illumination, etc., with the screw holes 612 formed in the mounting plate 600.

  FIG. 3 is a bottom view of the straight tube illumination device 500, and is a view of the straight tube illumination device 500 that is not attached to the attachment plate 600, as viewed from the bottom surface side. The fixture 502 and the fixture 504 are provided with screw holes 548 for fixing the straight tube illumination device 500 and further with communication holes 544 connected to the inside of the straight tube LED lamp unit 510. Although not shown, the power cord can be drawn out through the communication hole 544 of either the attachment 502 or the attachment 504.

  4 is a cross-sectional view taken along the line AA of FIG. 1, which is a cross-sectional view with respect to the mounting tool 504, but the mounting tool 502 has the same shape, and will be described with reference to a cross-sectional view of the mounting tool 504. The screw hole 548 shown in FIG. 3 is provided with a chamfer 545 at the opening on the lamp fixing portion 522 side. The support body 532 has a communication hole 544 formed therein.

  FIG. 5 is an explanatory diagram for explaining a connection structure between the cylindrical case 512 and the attachment 502 of the straight tube lighting device 500, FIG. 6 is a cross-sectional view taken along the line BB of FIG. 5, and FIG. It is -C sectional drawing. The fixing structure of the straight tube type LED lamp unit 510 and the mounting tool 502 is the same as the fixing structure of the straight tube type LED lamp unit 510 and the mounting tool 504, and the fixing of the straight tube type LED lamp unit 510 and the mounting tool 502 is representative. The structure will be described. The fixture 502 has two spaces with different inner diameters, and the two spaces are a first space 328 and a second space 329. The inside of the first space 328 is made slightly larger than the outer periphery of the end portion of the straight tube type LED lamp portion 510, and the end portion of the straight tube type LED lamp portion 510 is inserted into the first space 328. The second space 329 is shorter in the radial direction than the first space 328 and has a dimensional relationship in which the end of the straight tube LED lamp portion 510 cannot be inserted. For this reason, a step 330 is formed at the connecting portion between the first space 328 and the second space 329, and the end of the straight tube type LED lamp unit 510 is positioned at the position of the step 330. The fixing structure of the straight tube type LED lamp unit 510 and the mounting tool 502 is the same in the fixing structure of the straight tube type LED lamp unit 510 and the mounting tool 504, and the straight tube type LED is formed at the step 330 inside the mounting tool 504. The insertion position of the end portion of the lamp portion 510 is determined.

  By attaching the fixture 502 or the fixture 504 and each end of the straight tube type LED lamp unit 510 in a secret manner, the fixture 502 or the fixture 504 and each end of the straight tube type LED lamp unit 510 are secured. Can prevent dust and moisture from entering. Further, it is desirable to fix the fixture 502 or fixture 504 and the straight tube type LED lamp portion 510 so as not to move with respect to each other. For this reason, it is desirable to fix the first space 328 formed in the fixture 502 or the fixture 504 and the end of the straight tube LED lamp portion 510 with an adhesive.

  FIG. 7 is a CC cross section of FIG. 5 and shows the internal structure of the straight tube type LED lamp portion 510. Two grooves 326 are formed along the long axis of the straight tube type LED lamp portion 510 in a positional relationship facing the left and right inner surfaces of the cylindrical case 512 shown in FIG. For example, the grooves 326 are formed between the protrusions 322 and 323 by providing the protrusions 322 and 323 on the left and right inner surfaces of the cylindrical case 512, respectively. A resin substrate 570 is inserted and fixed between the two opposing grooves 326. As described above, since the length in the major axis direction of the resin substrate 570 is longer than the length in the major axis direction of the cylindrical case 512 of the straight tube type LED lamp portion 510, both ends of the cylindrical case 512 that are open are opened. However, the end portions of the resin substrate 570 protrude.

FIG. 7 is a cross-sectional view taken along the line CC of FIG. 5 and is formed inside the lamp fixing portion 520 of the fixture 502 so that the grooves 334 are opposed to the left and right in FIG. The grooves 334 may be formed directly on the inner surface of the outer wall of the lamp fixing portion 520, or as shown in FIG. 7, protrusions 324 are formed on the left and right of the inner surface of the outer wall of the lamp fixing portion 520, respectively. 334 may be formed. Since the grooves 334 formed on the left and right of the inner surface of the outer wall of the lamp fixing portion 520 are formed in a positional relationship connected to the groove 326 shown in FIG. 6, the length of the resin substrate 570 protruding left and right from the cylindrical case 512 is long. As shown in FIG. 7, both end portions in the direction along the axis are inserted into two grooves 334 formed in an opposing positional relationship.
As shown in FIGS. 5 and 7, the thickness cross-sectional area of the support 530 is smaller than the arbitrary cross-sectional area of the elongated portion of the cylindrical case 512.

  The end of the cylindrical case 512 is fixed with an adhesive to the outer wall of the first space 328 inside the lamp fixing part 520 or the lamp fixing part 522, and a resin substrate 570 is a groove formed in the cylindrical case 512. 326 is inserted and fixed, and the end of the resin substrate 570 is inserted into the groove 334 formed in the lamp fixing part 520 or the lamp fixing part 522, so that the cylindrical case has high reliability. 512 and the attachment 502 or the attachment 504 are fixed. It can be fixed with much stronger strength than fixing with adhesive alone.

  The groove 326 shown in FIG. 6 may form a recess on the inner side of the cylindrical case 512 so as to dent the outer wall of the cylindrical case 512 from the inner side along the longitudinal axis. The structure in which the inner side of the outer wall of the cylindrical case 512 is recessed may reduce the strength of the cylindrical case 512 itself. In such a case, as shown in FIG. 6, the protrusion 322 and the protrusion 323 are provided on both sides of the groove 326 along the longitudinal direction of the cylindrical tube 446, so that the groove is formed between the protrusion 322 and the protrusion 323. 326 can be formed, which has an effect of increasing mechanical strength. The cylindrical case 512 may not be a perfect circle but may be an ellipse. For example, the mechanical strength in the rotational direction between the fixture 502 or the fixture 504 and the straight tube LED lamp portion 510 can be increased by adopting an elliptical shape.

  In the structure shown in FIGS. 5 to 7, since the inside of the cylindrical case 512 is open to the outside air through the first space 328, the second space 329, and the communication hole 544, the air inside the cylindrical case 512 is It can be appropriately replaced with the outside air. If the inside of the cylindrical case 512 is a sealed space, the humidity of the air inside the cylindrical case 512 changes depending on the outside air temperature, and condensation may occur when the outside air temperature becomes low. In the present embodiment, since the inside of the cylindrical case 512 is open to the outside air, there is an effect that it is difficult for condensation to occur. In addition, a change in the outside air temperature does not cause a pressure difference between the inside of the cylindrical case 512 and the outside air. Thus, reliability can be improved by the structure in which the inside of the cylindrical case 512 is connected to the outside air.

  FIGS. 8 to 10 show other embodiments of the mounting tool 502 and the mounting tool 504 described with reference to FIGS. 5 and 7. The basic structure is the same, but the detailed structure is different. FIG. 8 shows another embodiment of the fixture 502, but the fixture 504 has a similar structure. A first space 328 and a second space 329 are formed in the lamp fixing portion 520, and a step 330 is formed between the first spaces 328 and 239. When the end portion of the straight tube type LED lamp unit 510 is inserted, the end portion of the straight tube type LED lamp unit 510 hits the step 330, so that the step 330 acts as a positioning member. The resin substrate 570 protrudes from the end of the cylindrical case 512 of the straight tube type LED lamp unit 510, and the protruding end of the resin substrate 570 fits into the groove 334 shown in FIGS. The substrate 570 is fixed. By fitting the resin substrate 570 into the groove 334, the straight tube type LED lamp portion 510 and the fixture 502 are fixed. The attachment 504 has the same structure as the attachment 502, and the attachment 504 is the same. By fixing the inner side of the first space 328 and the end of the straight tube type LED lamp unit 510 with an adhesive, the end of the straight tube type LED lamp unit 510 and the fixture 502 or the fixture 504 are sealed. Can be firmly fixed. Similar to the above description, the air inside the straight tube type LED lamp unit 510 is opened to the outside air through the first space 328, the second space 329, and the communication hole 544.

  The groove 334 is formed using the thickness of the outer wall of the second space 329. As shown in FIG. 7, the protrusion 324 may be formed, and the groove 334 may be formed in the protrusion 324. The mounting tool 502 and the mounting tool 504 are integrally formed using resin as a material, and the mounting base 540 has a mesh-shaped uneven portion on its bottom surface as shown in FIG. 10 for reinforcement and warpage prevention. . With such a structure, a light and strong attachment 502 or attachment 504 can be obtained. Moreover, the secular change of shapes, such as curvature, can be suppressed.

2. Electrical component 30 provided on resin substrate 570
FIG. 11 shows a configuration of the electrical component 30 housed in the straight tube type LED lamp unit 510. A resistor 220, a peak current setting capacitor 222, a rectifier circuit 230, and a fuse 224 are provided at one end of the resin substrate 570. The LED circuits 254 connected in series over the entire resin substrate 570 are regularly arranged. Here, by providing nine or more LED circuits 254, as will be described below, it is possible to reliably ensure a current interruption period of the current flowing through the LED circuit 254, and to reduce temperature rise.

  In FIG. 11, for example, household AC power is supplied from a power cord 590 constituted by a lead wire 311 and a lead wire 312, and is led to the power terminal 208. An AC power source is led from the power supply terminal 208 to the drive circuit 550 through a wiring provided on the back surface of the resin substrate 570 (not shown), and is configured by nine or more LED circuits 254 connected in series from the drive circuit 550. A pulsating current is supplied to the group 250. The LED group 250 emits light by the supplied pulsating current.

  In this embodiment, the LED circuits 254 are arranged in a grid pattern. Of course, they may be arranged in a straight line, but by arranging the LED circuits 254 in a grid shape in this way, unevenness in light emission can be reduced. In FIG. 11, the peak current setting capacitor 222 is composed of one ceramic capacitor, but a plurality of ceramic capacitors may be connected in parallel as necessary. In order to extend the life, it is desirable to use a ceramic capacitor. Ceramic capacitors are small and have an excellent feature of long life. However, the obtained capacity has a disadvantage that it is smaller than that of an electrolytic capacitor. Therefore, a single ceramic capacitor may be used, but if necessary, a plurality of capacitors may be connected in parallel to compensate for the above disadvantages, and the peak current setting capacitor 222 may be configured.

  In the embodiment of the present application, the LED circuit 254 and the drive circuit 550 generate very little heat, and it is not necessary to provide a metal plate for heat conduction on the resin substrate 570. In addition, since the LED circuit 254 generates less heat, the LED element provided in the LED circuit 254 is less deteriorated and has a longer life. For this reason, there is no need to replace the straight tube type LED lamp unit 510 in a short period of time, and the fixture 502 and the fixture 504 are attached to the straight tube type LED lamp unit 510, and the straight tube type LED lamp unit 510 is attached to the ceiling, wall, etc. Can be installed where lighting is required.

3. Configuration and Operation of Drive Circuit 550 FIG. 12 is a circuit diagram showing an electric circuit of straight tube illumination device 500. The electric circuit 580 of the straight tube illumination device 500 includes an LED group 250 that generates light and a drive circuit 550 that supplies current for light emission. The LED group 250 is held by a resin substrate 570, and a plurality of LED circuits 254 are connected in series. As will be described later, by increasing the number of stages of LED circuits 254 connected in series, that is, the number of LED elements connected in series, the interruption period of the pulsating current flowing through the LED group 250 becomes longer. By ensuring a period during which the pulsating current flowing through the LED group 250 is cut off, heat generation can be reduced and the temperature rise of the LED elements can be suppressed. In the following embodiments, it is desirable that nine or more LED elements 252 are connected in series in order to ensure a cutoff period of the pulsating current flowing through the LED group 250.

In this specification, a circuit in which at least one or a plurality of LED elements 252 are connected in parallel is referred to as an LED circuit 254, and the number of LED circuits 254 connected in series is referred to as a stage. In the embodiment of FIG. 12, the LED circuit 254 is configured by parallel connection of three LED elements 252. Also that has LED circuit 254 is connected to about 30 in series. In this specification, this state is described as 30 stages of LED circuits 254 connected in series. If the LED circuits 254 are connected in series of 5 stages or more, preferably 9 stages or more, it is possible to secure an effective cutoff period for suppressing heat generation. In a general household 100 volt power supply, if the number of stages of the LED circuit 254 is too large, the time during which power can be supplied decreases too much, and it becomes difficult to secure the amount of light emission. For a 100 volt AC power supply, 40 stages or less is preferable, and 35 stages or less is preferable. In order to increase the number of LED elements 252 further, it is desirable to add the circuit configuration shown in FIG.

  The drive circuit 550 that supplies current to the LED group 250 includes a peak current setting capacitor 222, a rectifier circuit 230, and a fuse 224, which are connected in series. In addition, a resistor 220 for discharging the accumulated charge of the peak current setting capacitor 222 is connected in parallel to the peak current setting capacitor 222. Further, a power terminal 208 is provided, and AC power is supplied to the power terminal 208 from the AC power source 100 via the power cord 590 described above. It is dangerous if the electric charge of the peak current setting capacitor 222 when the power is shut off is held without being discharged. When the power is turned on again, the inrush current when the power is turned on may become a dangerous value in relation to the charge held in the peak current setting capacitor 222. For this reason, it is desirable to discharge the accumulated charge of the peak current setting capacitor 222 as soon as possible when the power is shut off. A resistor 220 is provided for this purpose.

  FIG. 13 shows operation waveforms of the circuit shown in FIG. This operation waveform is the result of simulating the circuit shown in FIG. 12 using the simulation program QCS provided by the University of Yamanashi. The simulation condition is that the AC power supply of the AC power supply 100 is 50 cycles, the peak voltage is 144 volts, the peak current setting capacitor 222 is 1 μF, the resistor 220 is 100 KΩ, the resistance of the fuse 224 is 100Ω, and the number of stages of the LED circuit 254 is 32. Stepped. In order to avoid an excessive state, the simulation is started after 0.02 seconds have elapsed, and the state up to 0.07 seconds is shown.

  The characteristic diagrams and various waveforms shown below are all the results of simulation using the simulation program QCS provided by the University of Yamanashi.

  A waveform V102 is a voltage waveform of the AC power supply 100, and a waveform V104 is a terminal voltage waveform of the peak current setting capacitor 222. The current I2 is a current supplied to the input terminal 232 of the full-wave rectifier circuit 230. The current I2 is full-wave rectified by the full-wave rectifier circuit 230, and the pulsating current is supplied to the LED group 250. The horizontal axis is time and the unit is seconds.

  The characteristic of the LED element 252 of the LED circuit 254 is that when the forward applied voltage of the LED element 252 is gradually increased from almost zero volts, the forward applied voltage starts to flow and the current starts to flow when the voltage VLC is exceeded. , Start to emit light. On the other hand, when the voltage is decreased, the current starts to flow and when the applied voltage becomes lower than the voltage VLC, the current is cut off and the light emission action is stopped.

  In FIG. 13, although not shown in the waveform in a state before 0.02 seconds, when the forward applied voltage of the LED group 250 becomes lower than the voltage obtained by multiplying the voltage VLC by the number of series stages of the LED circuit 254, the LED The current through group 250 has stopped. In the state of FIG. 13, the peak current setting capacitor 222 holds a voltage lower than the voltage that causes the current to flow through the LED group 250. That is, the voltage applied to each LED element 252 is maintained in a state where the current starts flowing through each LED element 252 and is lower than the voltage VLC. This is the same state as at 0.027 seconds. As the AC power gradually approaches zero volts, the supply voltage to the LED group 250 increases.

  The voltage waveform V102 of the AC power supply 100 increases from 0.02 seconds, and the AC voltage supplied from the AC power supply 100 is added to the terminal voltage of the peak current setting capacitor 222 that has been charged with a reverse polarity. Is supplied to the LED group 250. A current exceeding the voltage VLC is applied to each LED element 252 of the LED group 250, and a current starts to flow to each LED element 252 of the LED group 250, and each LED element 252 of the LED group 250 emits light. Start. In 0.025 seconds, the voltage waveform V102 of the AC power supply 100 reaches a peak, the forward voltage applied to the LED group 250 decreases, and when the voltage applied to each LED element 252 starts to flow and becomes lower than the voltage VLC, it flows through the LED group 250. The current I4 is cut off. In this way, a period during which the current I4 flowing through the LED group 250 is interrupted occurs every half cycle of the AC power supply. As will be described below, the reduction characteristic and the cutoff timing of the current I4 flowing through the LED group 250 are constant regardless of the number of stages of the LED group 250. On the other hand, the current flow start time is delayed as the number of LED groups 250 increases. Accordingly, the period between the time point when the current I4 flowing through the LED group 250 is cut off and the time point when the current begins to flow becomes longer as the number of stages of the LED group 250 increases. Next, this relationship will be described.

4). The interruption period of the current I4 flowing through the LED group 250 and the number of series connection stages of the LED elements 252 The period during which the current I4 flowing through the LED group 250 is interrupted is the number of LED elements 252 constituting the LED group 250, that is, the LED circuit 254. It depends on the number of steps. FIG. 14 is a graph showing the state of the current interruption period of the current I4 flowing through the LED group 250 when the number of stages of the LED circuit 254 is changed. The current I4 of the LED group 250 flows every half cycle of the power supply waveform. The end timing of the current I4 is roughly the same regardless of the number of stages of the LED circuit 254, and the timing at which the current starts to flow varies depending on the number of stages of the LED circuit 254. When the number of stages of the LED circuit 254 is 32, the current starts to flow after the peak point of the current I4 of the LED group 250, so that the peak value of the current I4 of the LED group 250 is reduced, but this starts to flow. This is because the point was delayed. When the number of stages constituting the LED group 250, that is, the number of series-connected LED elements 252 is reduced, the current start point of the current I4 of the LED group 250 moves forward, and at the stage number 20, it starts to flow before the peak point of the current I4. When the number of stages 20 of the LED group 250 is further reduced to 10 stages, the current start point of the current I4 of the LED group 250 moves further forward. Thus, since the current end point of the current I4 of the LED group 250 is constant regardless of the number of stages, if the number of stages is decreased and the current start point of the current I4 is moved forward, the interruption period of the current I4 of the LED group 250 is shortened. .

  Increasing the cutoff period reduces the heat generation period of the LED group 250. Therefore, by increasing the number of stages, the starting point of the current I4 can be delayed, the interruption period can be increased, and the amount of heat generated by the LED element 252 can be reduced. However, since the light emission period also decreases, it is desirable to set the number of stages appropriately and maintain the relationship between the light emission amount and the heat generation in an appropriate relationship.

5. In FIG. 14, the peak value of the current I4 of the LED group 250 and the graph of the number of stages 20 in FIG. Since the graph of 32 stages rises after the peak value of the current I4 has passed, the peak value of the current I4 has decreased. Therefore, if the number of stages at which the current I4 starts to flow before the peak value of the current I4, the peak value of the current I4 is constant regardless of the number of LED elements 252 connected in series. The maximum light emission amount of the LED element 252 is determined by the peak value of the current I4. Therefore, if the number of stages starts to flow the current I4 before the peak value of the current I4, the maximum light emission amount of the LED element 252 is the same regardless of the number of stages.

6). Control of Peak Value of Current I4 Flowing through LED Group 250 FIG. 15 is a circuit shown in FIG. 12, where the resistance 220 connected in parallel to the peak current setting capacitor 222 is 1 MΩ, the resistance of the fuse 224 is 100Ω, and the peak current It is a graph which shows the change of the peak value of the electric current I4 of the LED group 250 at the time of changing the capacity | capacitance of the capacitor 222 for a setting from 0.1 micro F to 20 micro F. When the capacity of the peak current setting capacitor 222 is increased, the peak value of the current I4 of the LED group 250 is greatly increased accordingly. That is, the peak value of the current I4 of the LED group 250 is determined by the capacity of the peak current setting capacitor 222.

  16 and 17 show a case where the resistance 220 connected in parallel to the peak current setting capacitor 222 is 10 KΩ, the resistance of the fuse 224 is 100 Ω, and the capacitance of the peak current setting capacitor 222 is gradually increased from 0.001 μF. It is a graph which shows the change of the peak value of the electric current I4 of the LED group 250 of. The range from 0.001 μF to 0.025 μF is an area where the peak value of the current I4 of the LED group 250 decreases when the capacitance of the peak current setting capacitor 222 is increased. On the other hand, when the capacity of the peak current setting capacitor 222 exceeds 0.025 μF, the peak value of the current I4 of the LED group 250 increases rapidly as the capacity increases. However, this graph shows a change in the peak value of the current I4 of the LED group 250 with respect to the capacity of the capacitor 222 for setting the peak current. In order to issue the LED group 250 as illumination, a larger current is supplied as the current I4. It is necessary.

  When the capacity of the peak current setting capacitor 222 is further increased, the peak value of the current I4 of the LED group 250 increases rapidly as the capacity of the peak current setting capacitor 222 increases to 20 μF as shown in FIG. . When the capacitance of the peak current setting capacitor 222 exceeds 50 μF, the peak value of the current I4 of the LED group 250 hardly increases.

  In order to operate the LED group 250 as a lighting device, it is desirable to supply a current of 50 mA or more. According to FIG. 17, the capacitance of the peak current setting capacitor 222 is about 0.5 μF or more.

  16 and 17, the peak current setting capacitor 222 is charged in a region of 0.025 μF or more where the peak value of the current I4 of the LED group 250 increases based on the capacity of the peak current setting capacitor 222. By discharging the electric charge, the current I4 is supplied to the LED group 250, and the heat generation of the drive circuit 550 is reduced. The peak value of the current I4 of the LED group 250 shown in FIG. 14 can be set based on the capacity of the peak current setting capacitor 222, and the emission intensity of the LED group 250 is set and controlled by the capacity of the peak current setting capacitor 222. can do. On the other hand, as described with reference to FIG. 14, the interruption period of the current I 4 of the LED group 250 can be set and controlled by the number of LED elements 252 constituting the LED group 250 connected in series, that is, the number of stages of the LED group 250.

  FIG. 18 shows the case where the resistance 220 connected in parallel to the peak current setting capacitor 222 is 1.5 KΩ, the resistance of the fuse 224 is 100 Ω, and the capacitance of the peak current setting capacitor 222 is changed from 0.01 μF to 20 μF. It is a graph which shows the change of the peak value of the electric current I4 of the LED group 250 of. Up to about 0.5 μF, even if the capacity of the peak current setting capacitor 222 is increased, the peak value of the current I4 of the LED group 250 hardly changes. However, when the capacity is increased beyond 0.5 μF, the peak value of the current I4 of the LED group 250 greatly increases. In the region where the peak value of the current I4 of the LED group 250 increases by increasing the capacity of the peak current setting capacitor 222, the heat generation of the drive circuit 550 can be significantly reduced.

  FIG. 19 is a circuit shown in FIG. 12, in which the capacity of the peak current setting capacitor 222 is 1 μF, the resistance of the fuse 224 is 100Ω, and the resistance 220 connected in parallel to the peak current setting capacitor 222 is 1 KΩ to 50 KΩ. It is a graph which shows the change of the peak value of the electric current I4 of the LED group 250 at the time of changing. The resistor 220 is a discharge resistor for discharging the electric charge stored in the peak current setting capacitor 222 when the power is shut off. If the resistor 220 is not provided, the peak current setting capacitor is turned off when the power switch is turned off. The charge charged in 222 is maintained as it is. In actuality, it is thought that leakage occurs little by little, but electric charge is stored in the peak current setting capacitor 222 for a long time. When the power switch is turned on again after the power supply is shut off and the discharge of the peak current setting capacitor 222 is not completed, the supply voltage when the power is turned on and the charge stored in the peak current setting capacitor 222 May cause a large transient current to flow in the circuit component, for example, the LED element 252, and the LED element 252 may be damaged. Therefore, it is desirable to discharge the charge of the peak current setting capacitor 222 through the resistor 220 in a short time when the power switch is cut off.

  When the resistance value of the resistor 220 is gradually increased from 2 KΩ, the peak value of the current I4 of the LED group 250 decreases. This is because the current flowing through the resistor 220 decreases and the impedance of the parallel circuit of the peak current setting capacitor 222 and the resistor 220 increases. However, a characteristic phenomenon occurs when the resistance value of the resistor 220 is 3 KΩ or more, particularly exceeding 5 KΩ. That is, as the resistance value increases, the value of the current I4 flowing through the LED group 250 is flat or slightly increased. This seems to be related to the charge / discharge of the peak current setting capacitor 222 and the phase of the power supply voltage.

  Thus, in the state where the peak value of the current I4 of the LED group 250 is leveled or slightly increased regardless of the increase in the resistance value, it is considered that the heat generation by the resistor 220 is very small. Therefore, it is desirable to set the resistance value of the resistor 220 to a value in a region where the peak value of the current I4 of the LED group 250 is leveled or slightly increased regardless of the increase in the resistance value of the resistor 220. In the region where the peak value of the current I4 of the LED group 250 decreases as the resistance value of the resistor 220 increases, it is considered that the heat generation of the resistor 220 is large. On the other hand, in the region where the peak value of the current I4 of the LED group 250 is flat or slightly increased regardless of the increase in the resistance value of the resistor 220, the heat generation of the resistor 220 is very small and the heat generation of the drive circuit 550 is very small. .

  FIG. 20 shows a resistor connected in series with the peak current setting capacitor 222. In this embodiment, the fuse 224 has a resistance of 100Ω, the peak current setting capacitor 222 has a capacitance of 1 μF, and the resistor 220 has a resistance of 1MΩ. The simulation result of the transient current which flows into the LED group 250 when the voltage of 75V is sometimes applied is shown. A peak current that is approximately twice the steady state peak current flows. Actually, in the worst case, a voltage of 144 V may be applied when a current is applied, and a peak current about four times that in a steady state may flow. If the resistance connected in series to the peak current setting capacitor 222 is further reduced, there is a possibility that a larger electric current flows.

  FIG. 21 shows a resistor connected in series with the peak current setting capacitor 222. In this embodiment, the fuse 224 has a resistance of 50Ω, the peak current setting capacitor 222 has a capacitance of 1 μF, and the resistor 220 has a resistance of 1 MΩ. The simulation result of the transient current which flows into the LED group 250 when the voltage of 75V is sometimes applied is shown. Compared to the case shown in FIG. 20, in the case shown in FIG. 21, a larger peak current flows with respect to the peak current in the steady state. A prototype was actually made and tested when the resistance of the fuse 224 was 50Ω and when the resistance of the fuse 224 was 100Ω, and it was confirmed that the LED elements 252 constituting the LED group 250 were not damaged. However, in this embodiment, if the resistance of the fuse 224 is set to a value smaller than 50Ω, a large inrush current flows, which is very dangerous.

  FIG. 22 is a graph showing a change in the peak value of the current I4 flowing through the LED group 250 when the resistance connected in series to the peak current setting capacitor 222, in this embodiment, the resistance of the fuse 224 is changed from 50Ω to 10KΩ. It is. When the value of the resistor connected in series to the peak current setting capacitor 222 is increased, the peak value of the current I4 flowing through the LED group 250 decreases accordingly. In a state where the peak value of the current I4 flowing through the LED group 250 decreases, this means that the resistor connected in series to the peak current setting capacitor 222 generates heat, and the drive circuit 550 generates heat. In this case, since the maximum light emission amount of the LED group 250 is reduced, it is desirable to reduce the value of the resistor connected in series to the peak current setting capacitor 222 as much as possible. Although two types of 50Ω and 100Ω have been prototyped and it has been confirmed that there is no failure due to inrush current, it is possible to use even larger values than the resistance values of 50Ω and 100Ω. The resistor connected in series to the peak current setting capacitor 222 acts to suppress the inrush current when the power is turned on, and the effect of suppressing the inrush current is greater when the resistance value is larger. When these things are judged comprehensively, the resistance connected in series to the peak current setting capacitor 222 is preferably in the range of 50Ω to 1KΩ. In the graph shown in FIG. 22, when a 1 KΩ resistor is used, the peak value of the current I4 flowing through the LED group 250 decreases, but is in a usable range.

  Judging from the graph of FIG. 22, when the resistance connected in series to the peak current setting capacitor 222 is 500Ω, the peak value of the current I4 flowing through the LED group 250 does not decrease so much. Therefore, it is very good if the resistance connected in series to the peak current setting capacitor 222 is in the range of 50Ω to 500Ω.

7). FIG. 23 is a circuit diagram shown in FIG. 12 in which the peak current setting capacitor 222 is 5 μF, the resistance value of the resistor 220 is 1 MΩ, and the resistance value of the fuse 224 is 100Ω. The waveforms of the current I4 flowing through the LED group 250 when the number of stages 250 is two and nine are shown. The peak value of the waveform of the current I4 when the number of stages is two and nine is almost the same. The current interruption period is different, and in the case of two stages, there is almost no interruption period of the current I4, whereas in the case of nine stages, the interruption period of the current I4 is reliably ensured.

  That the peak value of the current I4 is substantially the same means that the maximum light emission amounts of the LED elements 252 constituting the LED group 250 are substantially the same. On the other hand, the area defined by the waveform of the current I4 is greatly related to heat generation, and the area based on the difference between the two-stage current waveform and the nine-stage current waveform means the difference in heat generation. This shows that the amount of heat generation is much reduced when the LED group 250 is composed of nine stages, compared with the two stages.

  By increasing the number of stages of the LED elements 252 constituting the LED group 250 connected in series to more than 9, the maximum light emission amount of the LED elements 252 can be made the same and the heat generation amount can be surely reduced.

  DESCRIPTION OF SYMBOLS 100 ... AC power supply, 220 ... Resistance, 222 ... Peak current setting capacitor, 230 ... Rectifier circuit, 224 ... Fuse, 250 ... LED group, 252 ... LED element, 254 ... LED circuit, 322 ... protrusion, 323 ... protrusion, 326 ... groove, 328 ... first space, 329 ... second space, 324 ... protrusion, 330 ... -Step, 334 ... Groove, 510 ... Straight tube type LED lamp part, 512 ... Cylindrical case, 502 ... Attachment, 504 ... Attachment, 520 ... Lamp fixing part, 522: Lamp fixing part, 530: Support, 532 ... Support, 540 ... Mounting base, 542 ... The mounting base, 550 ... Drive circuit, 570 ... Resin Substrate, 580 ... Electric circuit, 590 ... the power cord, 600 ... mounting plate.

Claims (8)

An elongated cylindrical resin containing an LED group configured by connecting a plurality of LEDs that emit light in series based on a supplied light emission current and a drive circuit for supplying the light emission current to the LED group A straight tube type LED lamp part formed with a case, and first and second attachments respectively provided at both ends of the straight tube type LED lamp part,
The drive circuit includes a peak current setting capacitor, a parallel resistor connected in parallel to the peak current setting capacitor to form a parallel circuit together with the peak current setting capacitor, and an alternating current input from an input terminal. A full-wave rectifier circuit that rectifies the wave and outputs a pulsating current from an output terminal, the parallel circuit configured by the peak current setting capacitor and the parallel resistor, and an input terminal of the full-wave rectifier circuit When, are connected in series to an AC power source,
The LED group is connected between the output terminals of the full-wave rectifier circuit,
Has a projection projecting inside the tubular resin case is molded one body, the resin substrate is held by the projections, the LED group is arranged which has the driving circuit on the surface of the resin substrate ,
The first and second attachments are respectively a lamp fixing part for fixing an end of the cylindrical resin case of the straight tube type LED lamp part, and a mounting base for attaching the straight tube type LED lamp part. The support that connects the lamp fixing part and the mounting base is integrally formed by resin molding, and the thickness cross-sectional area of the support is arbitrary for the elongated part of the cylindrical resin case. The support is formed in a shape smaller than the cross-sectional area,
The tube-shaped resin case of the straight tube type LED lamp portion has an end bonded to the lamp fixing portion with an adhesive, and the straight tube type LED lamp portion and the first and second resin molded integrally . The fixtures are fixed to each other as a unit, and are attached to a place where lighting is performed, and are configured to be replaceable .
When the number of LEDs connected in series constituting the LED group connected between the output terminals of the full-wave rectifier circuit is the number of stages, the LED group is formed in any number of stages from 5 to 40 stages. The capacitance of the capacitor for setting the peak current constituting the parallel circuit is set to a value within a range of 0.5 microfarad to 20 microfarad, and the resistance value of the parallel resistor constituting the parallel circuit is set to 3 KΩ or more. The pulsating current flows through the LED group, with a peak current value determined based on the capacitance of the capacitor for setting the peak current, and having a cutoff period determined by the number of stages of the LEDs connected in series constituting the LED group. configuration was, straight-tube lighting apparatus, characterized in that the.   2. The straight tube type lighting device according to claim 1, wherein the mounting plate has an elongated shape with an area for accommodating the flat surface of the straight tube type LED lamp portion in a plane viewed from above, and the first and second mountings are provided. A straight-tube illuminating device, which is fixed to a fixture and attached to a place where illumination is performed in a state where the mounting plate is fixed and can be replaced.   3. The straight tube illumination device according to claim 1, wherein the projection provided on the cylindrical resin case has a groove in a longitudinal direction, and the resin substrate is inserted into the groove. A straight tube illumination device characterized by holding a resin substrate.   4. The straight tube illuminating device according to claim 1, wherein an uneven portion is formed on the bottom surface of the mounting base. 5. 5. The straight tube illumination device according to claim 1, wherein the lamp fixing portions of the first and second fixtures are respectively in the tubular shape of the straight tube LED lamp portion. has a larger hole periphery of the end portion of the resin case, an end portion of the tubular resin case is inserted into the hole of the lamp holding portion, the end portion of the tubular resin casing into the hole of the lamp holding portion In the inserted state, the lamp fixing part and the end of the cylindrical resin case are closely fixed by an adhesive,
A projection integrated with the lamp fixing portion is formed inside the lamp fixing portion, a substrate fixing groove is formed on the protrusion, and both end portions of the resin substrate protrude to holes of the lamp fixing portion, respectively. The straight tube illumination device is inserted into the substrate fixing groove and fixed. 6. The straight tube lighting device according to claim 1, wherein the LED group connected in parallel to the output terminal of the full-wave rectifier circuit is any one of 9 to 40 stages. A straight-tube illumination device using LEDs, characterized in that it is formed of LEDs connected in series with the number of stages . The straight tube lighting device according to claim 6,
Each stage of the LED group is composed of the LEDs having a plurality of LED elements connected in parallel,
The LED group is configured by connecting the LEDs having the plurality of LED elements connected in parallel to each other in series in the number of stages, and is a straight tube illumination device using LEDs. A straight-tube lighting apparatus using an LED as claimed in claim 6 or claim 7, straight-tube lighting apparatus using the LED, characterized in that the peak current setting capacitor is a ceramic capacitor.

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